San Francisco’s Air Quality Matches Beijing’s

Bloomberg: Air quality in San Francisco sank to the level of smog-choked Beijing this week, as soot from more than a dozen wildfires in California’s wine country blanketed the Bay Area.

As San Francisco residents woke up to a hazy sky for the fifth day in a row, the concentration of dangerous particulate matter was forecast to be 158 on the air-quality index, according to the Bay Area Air Quality Management District. That’s roughly on par with notoriously smoggy Beijing, which clocked in at 165. Professor John Balmes is quoted.